Method for fabricating semiconductor component with thnned substrate having pin contacts

ABSTRACT

A semiconductor component includes back side pin contacts fabricated using a circuit side fabrication method. The component also includes a thinned semiconductor die having a pattern of die contacts, and conductive members formed by filled openings in the die contacts and the die. In addition, the pin contacts are formed by terminal portions of the conductive members. The fabrication method includes the steps of forming the openings and the conductive members, and then thinning and etching the die to form the pin contacts. An alternate embodiment female component includes female conductive members configured to physically and electrically engage pin contacts on a mating component of a stacked assembly.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of Ser. No. 10/933,144 filed Sep. 02,2004, which is a continuation of Ser. No. 10/457,774 filed Jun. 10,2003,Pat. No. 6,828,175 B2, which is a division of Ser. No. 10/232,549filed Aug. 29, 2002, Pat. No. 6,903,442 B2.

This application is related to Ser. No. 10/841,648 filed May 10, 2004,and to Ser. No. 11/208,304 filed Aug. 19, 2005.

FIELD OF THE INVENTION

This invention relates generally to semiconductor manufacture andpackaging. More particularly, this invention relates to a semiconductorcomponent with backside contacts, to a method for fabricating thecomponent, and to systems incorporating the component.

BACKGROUND OF THE INVENTION

Semiconductor components, such as chip scale packages and bumped dice,are being manufactured with a smaller outline and with a higher pincount than conventional plastic or ceramic packages. This type ofsemiconductor component typically includes a dense area array ofterminal contacts, such as solder bumps in a ball grid array (BGA) ormetal pins in a pin grid array (PGA). The terminal contacts permit thecomponent to be surface mounted to a supporting substrate, such as apackage substrate, a module substrate or a circuit board.

The quality, reliability and cost of these types of components is oftendependent on the fabrication method. The formation of the terminalcontacts and the electrical paths between the terminal contacts and thedice are a particular concern. In particular, reliable electricalinterconnections must be made between the terminal contacts for thecomponent, and contacts on the dice contained within the component.Typically, the die contacts comprise thin film aluminum bond pads inelectrical communication with integrated circuits on the dice.

Some prior art components require relatively complicatedinterconnections, such as metal beams or wires, formed of gold, goldplated materials, aluminum, copper or solder using a bonding process,such as thermosonic bonding or wire bonding. The interconnections, andtheir bonds with the die contacts and the terminal contacts, aresubjected to stresses during manufacture, and during subsequent use ofthe component. These stresses can cause the interconnections to weakenor pull apart, adversely affecting the reliability of the components.

The present invention is directed to an improved semiconductor componenthaving novel backside contacts and conductive member interconnections.In addition, the present invention is directed to a novel wafer levelfabrication method for manufacturing the component in volume usingconventional equipment.

SUMMARY OF THE INVENTION

In accordance with the present invention, an improved semiconductorcomponent, a method for fabricating the component, and electronicassemblies incorporating the component are provided.

The component includes a semiconductor die having a thinnedsemiconductor substrate with a circuit side (front side) and a backside. The die includes integrated circuits and a pattern of die contactson the circuit side in electrical communication with the integratedcircuits. In a first embodiment (male version), the component includesan array of pin contacts on the backside, and conductive members in thesubstrate in electrical communication with the die contacts and the pincontacts. Each conductive member is formed by an opening in a diecontact and substrate and a conductive material in the opening. Inaddition, each conductive member is exposed on the back side of thesubstrate to form a pin contact. The component can also includeredistribution conductors and contacts on the circuit side in electricalcommunication with the conductive members.

In a second embodiment (female version) the conductive members compriseopenings having insulated sidewalls plated with a conductive material.In this embodiment the conductive members are configured for matingphysical and electrical engagement with a pin contact on an adjacentcomponent of a stacked assembly.

The method for fabricating the component includes the step of providingmultiple semiconductor dice on substrate, such as a semiconductor wafer,having a circuit side and a back side. The method also includes thesteps of forming openings in the die contacts and part way through thesubstrate, forming an electrically insulating passivation layer on thecircuit side and in the openings, and depositing a conductive materialin the openings to form the conductive members. In addition, the methodcan include the steps of thinning and etching the substrate from theback side to expose terminal portions of the conductive members formingthe pin contacts, and then singulating the dice from the wafer. Themethod can also include the steps of forming redistribution conductorson the circuit side in electrical communication with the conductivemembers and circuit side contacts on the redistribution conductors.

With the method the pin contacts are formed on the back side of thecomponent using steps performed predominantly on the circuit side of thecomponent. Advantageously, the pin contacts provide electricalconnection points for performing various wafer level test procedures. Inaddition, the component can be integrated to form electronic assembliessuch as modules, circuit boards and stacked arrays.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1I are schematic cross sectional views illustrating steps in amethod for fabricating a male semiconductor component in accordance withthe invention;

FIG. 2A is a plan view taken along line 2A-2A of FIG. 1A illustratingsemiconductor dice on a wafer used in the fabrication method;

FIG. 2B is an enlarged plan view taken along line 2B-2B of FIG. 1Billustrating an opening in a die contact;

FIG. 2C is an enlarged view taken along line 2C of FIG. 1C illustratinga passivation layers in the opening and on the circuit side;

FIG. 2D is an enlarged view taken along line 2D of FIG. 1D illustratingan insulating layer on the circuit side;

FIG. 2E is an enlarged view taken along line 2E of FIG. 1E illustratinga conductive member and a redistribution conductor;

FIG. 2F is an enlarged view taken along line 2F of FIG. 1F illustratingthe conductive member following thinning of the wafer;

FIG. 2G is an enlarged view taken along line 2G of FIG. 1G illustratingthe conductive member and a terminal contact thereon following etchingof the wafer;

FIG. 2H is an enlarged view taken along line 2H of FIG. 1H illustratingcircuit side contacts on the component;

FIG. 2I is an enlarged view taken along line 2I of FIG. 1I illustratingthe completed male component;

FIG. 2J is an enlarged cross sectional view taken along section line2J-2J of FIG. 2A illustrating a die contact and integrated circuits onthe male component;

FIG. 2K is a cross sectional view taken along line 2K-2K of FIG. 1Eillustrating redistribution conductors on the male component;

FIG. 3A-3E are schematic cross sectional views of alternate embodimentsof the male component of FIG. 2I;

FIGS. 4A-4F are schematic cross sectional views illustrating steps in afabrication method for an alternate embodiment female component havingfemale conductive members;

FIG. 5A is an enlarged view taken along line 5A of FIG. 4A illustratingan opening in a die contact;

FIG. 5B is an enlarged view taken along line 5B of FIG. 4B illustratingpassivation layers;

FIG. 5C is an enlarged view taken along line 5C of FIG. 4C illustratingan insulating layer;

FIG. 5D is an enlarged view taken along line 5D of FIG. 4D illustratingredistribution conductors;

FIG. 5E is an enlarged view taken along line 5E of FIG. 4E illustratingan outer insulating layer;

FIG. 5F is an enlarged schematic cross sectional view illustrating thecompleted alternate embodiment female component; and

FIGS. 6A-6C are schematic cross sectional views illustrating electronicassemblies fabricated using components constructed in accordance withthe invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As used herein, the term “semiconductor component” refers to anelectronic element that includes a semiconductor die. Exemplarysemiconductor components include semiconductor packages, chip scalepackages, semiconductor dice, BGA devices, and semiconductor wafers.

Referring to FIGS. 1A-1I and 2A-2K, steps in the method for fabricatinga semiconductor component 16 (FIG. 2I) in accordance with the inventionare illustrated.

Initially, as shown in FIGS. 1A and 2A, a plurality of semiconductordice 10 are provided, for fabricating a plurality of semiconductorcomponents 16 (FIG. 2I). The dice 10 can comprise conventionalsemiconductor dice having a desired configuration. For example, each die10 can comprise a dynamic random access memory (DRAM), a static randomaccess memory (SRAM), a flash memory, a microprocessor, a digital signalprocessor (DSP) or an application specific integrated circuit (ASIC).The dice 10 and the components 16 can have any polygonal shape. In theillustrative embodiment, the dice 10 and the components 16 arerectangular in shape, but other polygonal shapes, such as square orhexagonal can also be utilized.

As shown in FIG. 2A, the dice 10 are contained on a semiconductor wafer12. Although in the illustrative embodiment, the method is performed onan entire semiconductor wafer 12, it is to be understood that the methodcan be performed on a portion of a wafer, on a panel, or on any othersubstrate that contains multiple semiconductor dice.

As shown in FIG. 1A, the wafer 12 and each die 10 includes asemiconductor substrate 14 having a circuit side 20 (front side or firstside) wherein integrated circuits 24 (FIG. 2J) are located, and a backside 22 (second side). The circuit side 20 and the back side 22 are themajor planar surfaces of each die 10. In addition, each die 10 includesa pattern of die contacts 18 formed on the circuit side 20, in aselected pattern, such as a dense area array, in electricalcommunication with the integrated circuits 24 (FIG. 2J) on the die 10.In the illustrative embodiment the die contacts 18 are the device bondpads for the die 10.

As shown in FIG. 2A, the die contacts 18 are generally square, planarpads having a desired size (e.g., 220-100 μm) and spacing. However,other polygonal shapes for the die contacts 18, such as rectangular, orcircular shaped can also be employed. For simplicity the die contacts 18are illustrated in a single row along the center of the die 10. However,the die contacts 18 can be arranged in any desired pattern includingsuch as edge connect, end connect, and dense area arrays such as gridarrays and micro grid arrays.

The die contacts 18 can comprise a conventional metal such as aluminum,copper and alloys thereof. As shown in FIG. 2J, an insulating layer 26on the circuit side 20, such as a layer of silicon dioxide, electricallyinsulates the integrated circuits 18 from the bulk of the substrate 14.

Next, as shown in FIGS. 1B and 2B, openings 28 are formed through thedie contacts 18 and part way through the substrate 14. The openings 28can be formed using an etching process, a laser machining process, anion milling process, or combinations of these processes. One method forforming the openings 28 combines etching and laser machining processes.For example, an etch mask (not shown) and an etching process can be usedto form the openings 28 through the die contacts 18. Depending on thematerial of the die contacts 18, a wet etchant can be used to etch thedie contacts 18. For die contacts 18 made of aluminum, one suitable wetetchant is H₃PO₄.

The die contacts 18 can also be made with the openings 28 therein. Forexample, the openings 28 can be formed during deposition of the diecontacts 18. In this case the etching and laser machining stepsdescribed above can be eliminated.

As shown in FIG. 2B, the openings 28 in the die contacts 18 aregenerally circular, and have an outside diameter OD that is smaller thanthe width W of the die contacts 18. In the illustrative embodiment,following formation of the openings 28, the die contacts 18 resemblesquare donuts having metal around their peripheries, but no metal in thecenter. Also in the illustrative embodiment, the diameter OD of theopenings 28 is about one half the width W of the die contacts 18. Inaddition, the openings 28 following the etching step, but prior to thelaser machining step, surround a portion of the substrate 14, such thatthe die contacts 18 and the openings 28 form targets, or a patternrecognition system, for a laser beam to counter bore the openings 28part way through the substrate 14. As shown in FIG. 2C, the openings 28can have a depth (D) of about 6 μm to 300 μm or greater, and a diameter(OD) of about 10 μm to 2 mils or greater.

One suitable laser system for performing the laser machining step ismanufactured by XSIL LTD of Dublin, Ireland, and is designated a modelno. XISE 200. Another suitable laser system for performing the lasermachining step is manufactured by Electro Scientific, Inc., of Portland,OR and is designated a Model No. 2700. A representative laser fluencefor forming the openings 28 through a silicon substrate having athickness of about 28 mils (711 μm), is from 2 to 10 watts/per openingat a pulse duration of 20-25 ns, and at a repetition rate of up toseveral thousand per second. The wavelength of the laser beam can be astandard UV wavelength (e.g., 355 nm).

Following the laser machining step, a cleaning step can be performed inwhich the openings 28 are cleaned using a suitable wet or dry etchant.One suitable wet etchant for cleaning the openings 28 with the substrate14 comprising silicon is tetramethylammoniumhydroxide (TMAH).

Next, as shown in FIGS. 1C and 2C, an electrically insulatingpassivation layer 30 is formed on the circuit side 20 of the wafer 12,and an electrically insulating passivation layer 32 is formed in theopenings 28. The passivation layer 30 electrically insulates the circuitside 20, and the passivation layer 32 electrically insulates theopenings 28. The passivation layers 30, 32 can comprise an electricallyinsulating material such as a glass, a polymer or an oxide formed as alayer of a required thickness. In the illustrative embodiment, thepassivation layers 30, 32 are a single layer of the same materialdeposited to a same thickness. However, the passivation layers 30, 32can be different materials deposited in different stages and withdifferent thicknesses.

As shown in FIG. 2C, the passivation layers 30, 32 have a thickness T1(FIG. 2C) that is less than the diameter OD of the openings 28, suchthat the sidewalls of the openings 28 are coated, but the openings 28are not completely closed. A thickness range for the passivation layers30, 32 can be from .10 μm to 100 μm or greater.

One suitable material for both passivation layers 30, 32 isborophosphosilicate glass (BPSG) which can be deposited to a requiredthickness using a spin-on or other suitable process. A photoimageablepolymer such as polyimide can also be deposited to a required thicknessusing a spin-on, electrophoretic or other suitable process.

As another example, parylene polymers can be deposited from the vaporphase by a process similar to vacuum metallization at pressures of about0.1 torr. Suitable polymers include parylene C, parylene N, and paryleneD. Parylene is available from Advanced Coating of Tempe, AZ. Onesuitable deposition apparatus for forming the passivation layers 30, 32of parylene is a portable parylene deposition system, designated a modelPDS 2010 LABCOATER 2, manufactured by Specialty Coating Systems, ofIndianapolis, IN.

The passivation layer 30 can also comprise a first electricallyinsulating material formed on the circuit side 20, and the passivationlayer 32 can comprise a second electrically insulating material formedin the openings 28. For example, the passivation layer 30 on the circuitside 20 can comprise a glass or a polymer layer formed as previouslydescribed, and the passivation layers 32 in the openings 28 can comprisesilicon dioxide formed using a growth or deposition process. Forexample, silicon dioxide can be grown by exposure of the siliconsubstrate 12 within the openings 28 to oxygen at an elevated temperature(e.g., 950° C.).

Next, as shown in FIGS. 1D and 2D, the passivation layers 30, 32 can bepatterned by etching, or other suitable process, to expose portions 34of the die contacts 18. A mask (not shown) having openings aligned withthe die contacts 18 can be used with a wet etchant to etch thepassivation layers 30, 32. For example, with the passivation layers 30,32 comprising BPSG one suitable etchant comprises HF. With thepassivation layers 30, 32 comprising parylene an oxygen plasma processor a laser ablation process rather than an etchant can be employed.

As also shown in FIG. 2D, an electrically insulating polymer layer 36 isformed on the circuit side 20 and patterned such that the exposedportions 34 of the die contacts 18 remain exposed. The polymer layer 36preferably comprises a low dielectric constant (low k) polymer such aspolyimide, polybenzoxazole (PBO), or benzocyclobutene (BCB). As usedherein, the term “low k” refers to a material with a dielectric constantof less than about 3.9.

The polymer layer 36 can be deposited to a desired thickness T2 using asuitable deposition process such as spin-on, positive displacementthrough a nozzle, screen printing or stenciling. Systems arecommercially available for performing each of these processes in thecontext of semiconductor packaging. For example, material dispensingsystems are manufactured by Asymtek of Carlsbad, Calif., and by Camalotof Cookson, UK. A representative range for the thickness T2 of thepolymer layer 36 can be from 10 μm to several mils.

Following deposition, the polymer layer 36 can be cured and thenpatterned by etching or other suitable process to expose the exposedportions 34 of the die contacts 18. For example, the polymer layer 36can comprise a photoimageable material, such as a low k resist. In thiscase, exposure and development of the polymer layer 36 forms openingsaligned with the die contacts 18.

Next, as shown in FIGS. 1E and 2E, a conductive material can bedeposited in the openings 28 to form conductive members 38. Theconductive material can comprise a highly conductive metal, such asnickel, gold, aluminum, titanium, iridium, copper, tungsten, silver,platinum, palladium, tantalum, molybdenum, tin, zinc and alloys of thesemetals. One of these metals can be deposited within the openings 28using a deposition process, such as electrolytic deposition, electrolessdeposition, or CVD. Alternately a solder metal can be screen printed inthe openings 28 and drawn into the openings 28 with capillary action ora vacuum.

As also shown in FIGS. 1E and 2E, redistribution conductors 40 can beformed on the circuit side 20 in electrical communication with the diecontacts 18 and the conductive members 38. As shown in FIG. 2K, theconductors 40 redistribute or “fan out” the pattern of the die contacts18. In addition, the conductors 40 include bonding pads 42, which in theillustrative embodiment are enlarged, generally planar segments withhemispherical edges located at the terminal ends of the conductors 40.The conductors 40 can be laid out such that the bonding pads 42 areconfigured in a desired pattern, such as a dense area array (e.g., gridarray). As such, the bonding pads 42 have a pattern that is differentthat the pattern of the die contacts 18. In addition, the bonding pads42 can be configured to select a “chip select” function in whichselected die contacts 18 can be addressed.

The conductors 40 and the bonding pads 42 preferably comprise a highlyconductive metal layer such as copper. In addition, the conductors 40and the bonding pads 42 can be formed using the same process andmaterials, or alternately can be formed separately. For example, coppercan be electrolessly plated on the polymer layer 36 in a requiredpattern and a required thickness T3 using techniques that are known inthe art. To perform the electroless plating process, the polymer layer36 can be initially cleaned, and the wafer 12 dipped in an aqueous bathcontaining a catalyst configured to form a copper seed layer. Catalystsystems are commercially available from Lea Ronal of Freeport, N.Y.under the trademark “UMT CATALYST SYSTEM”.

Following formation of the copper seed layer, a resist layer can beformed on the copper seed layer, and patterned to define the conductors40 and the bonding pads 42 in the required pattern. Suitable resists,such as electro deposited resists, are available from ShipleyCorporation of Newton, Mass. Next, the wafer 12 can be dipped in anelectroless (or an electrolytic) copper plating solution, such thatcopper is applied to areas of the seed layer not covered by the resist.One suitable plating solution can include “RONADEP” manufactured by LeaRonal and DI water. The copper can be electrolessly plated to form theconductors 40 and the bonding pads 42 with a thickness T3 of from about1 μm to 4 μm.

Following electroless copper plating, the resist can be stripped byplasma etching or other suitable process. In addition, the exposedcopper seed layer can be removed by etching, such that just theconductors 40 and the bonding pads 42 remain in the required pattern.

The outlined process for forming the conductors 40 and the bonding pads42 by electroless plating is merely exemplary, and other processes knownin the art can be employed to form the conductors 40 and the bondingpads 42 of copper or other metals, such as Al, Cr, Ti, Ni, W, Au, Ag,Ta, Mb. Other suitable deposition processes include CVD, PECVD, PVD,sputtering and evaporation. Also if desired, the conductive members 38,the conductors 40 and the bonding pads 42 can all be formed using thesame deposition process.

Next, as shown in FIGS. 1F and 2F, the wafer 12 is thinned from the backside 22 to expose the conductive members 38. The thinning step can beperformed using a mechanical planarization apparatus (e.g., a grinder).One suitable mechanical planarization apparatus is manufactured byOkamoto, and is designated a model no. VG502. The thinning step can alsobe performed using a chemical mechanical planarization (CMP) apparatus.A suitable CMP apparatus is commercially available from a manufacturersuch as Westech, SEZ, Plasma Polishing Systems, or TRUSI. The thinningstep can also be performed using an etch back process, such as a wetetch process, a dry etch process or a plasma etching process. Arepresentative thickness T4 of the substrate 14 following the thinningstep can be from 50 μm to 300 μm. As is apparent the thickness T4 isdependent on the depth D (FIG. 1B) of the openings 28.

Next, as shown in FIGS. 1G and 2G, the wafer 12 is etched back from theback side 22 to expose terminal portions of the conductive members 38and form pin contacts 44. The etch back step can be performed using awet etching process, a dry etching process or a plasma etching processsuch as reactive ion etching (RIE). In addition to removing portions ofthe substrate 14 and exposing terminal portions of the conductivemembers 38, the etch back step also removes corresponding portions ofthe passivation layers 32.

As also shown in FIGS. 1G and 2G, non-oxidizing layers 46 can be formedon the tips of the pin contacts 44. The non-oxidizing layers 46 cancomprise a non-oxidizing metal or metal alloy such as gold, agold/nickel alloy or platinum. In addition, the non-oxidizing layers 46can comprise bulbs that just coat the tips of the pin contacts 44, oralternately can cover all exposed surfaces thereof. The non-oxidizinglayers 46 can be formed using a deposition or plating process, such aselectroless deposition, electrolytic deposition or CVD. The completedpin contacts 44 can be used as the terminal contacts for the component16 and to surface mount the component 16. In addition, as will befurther explained, the pin contacts 44 can be used to physically andelectrically connect multiple components 16 in a stacked assembly (e.g.,assembly 68C-FIG. 6C). Further, prior to singulation of the wafer 12,the pin contacts 44 can be used to perform various wafer level testprocedures such as functionality testing, parametric testing, adherenceto required specifications testing and burn-in testing.

Next, as shown in FIGS. 1H and 2H, a back side polymer layer 48 can beformed on the thinned substrate 14. The back side polymer layer 48 cancomprise any of the polymer materials previously described for thepolymer layer 36. Alternately, the back side polymer layer 48 cancomprise a layer of vapor deposited parylene substantially as previouslydescribed for passivation layers 30, 32. During vapor deposition of theparylene, the pin contacts 44 can be protected using tape. Alternately,the pin contacts 44 can be coated with parylene which is can besubsequently stripped using a suitable stripper.

As also shown in FIGS. 1H and 2H, front side contacts 50 can be formedon the conductors 40 proximate to the conductive members 38, andredistribution contacts 52 can be formed on the bonding pads 42. Thecontacts 50, 52 can comprise metal bumps deposited on the conductors 40and bonding pads 42 using a suitable deposition process, such asstenciling and reflow of a solder alloy. The contacts 50, 52 cancomprise solder, another metal, or a conductive polymer material. Thecontacts 50, 52 can also be formed by electrolytic deposition, byelectroless deposition, or by bonding pre-fabricated balls to theconductors 40 and the bonding pads 42. For example, a ball bumper can beemployed to bond pre-fabricated balls. A suitable ball bumper ismanufactured by Pac Tech Packaging Technologies of Falkensee, Germany.The contacts 50, 52 can also be formed using a conventional wire bonderapparatus adapted to form a ball bond or a stud bump, and then to severthe attached wire.

As also shown in FIGS. 1H and 2H, an outer polymer layer 54 can beformed on the conductors 40 and contacts 50, 52. The outer polymer layer54 can comprise a low k polymer layer formed substantially as previouslydescribed for polymer layer 36. In addition, the outer polymer layer 54and the contacts 50, 52 can be planarized to a same planar surface usinga grinding or a chemical mechanical planarization process substantiallyas previously described for thinning the substrate 14. The planarsurface facilitates subsequent processes such as singulation, surfacemounting and stacking of the component 16. In addition to providingelectrical insulation and protection, the outer polymer layer 54 alsofunctions to rigidify and strengthen the attachment of the contacts 50,52 to the conductors 40 and the bonding pads 42.

Next as shown in FIGS. 1I and 2I, a singulating step is performed tosingulate the components 16 from the wafer 12 and from one another. Thesingulating step can be performed by attaching the wafer 12 to a dicingtape 56 and sawing grooves 58 through the wafer 12 using a conventionaldicing saw. Alternately the singulating step can be performed byetching, water jetting or other suitable process.

As shown in FIG. 2I, a singulated component 16 includes the thinned die10 having the die contacts 18 in electrical communication with theintegrated circuits 24 (FIG. 2J) thereon. The component 16 also includesthe planarized contacts 50, 52 on the circuit side 20 in electricalcommunication with the die contacts 18. The contacts 50, 52 can be usedto selectively access the integrated circuits 24 for testing or otherfunctions. In addition, for some applications the contacts 50, 52 can beused as the terminal contacts for the component 16.

The component 16 also includes the conductive members 38 in electricalcommunication with the die contacts 18, and the pin contacts 44 on theback side 22 of the die 10 in electrical communication with theconductive members 38. As previously stated, the pin contacts 44 can bearranged in a desired dense area array such as a pin grid array (PGA) ora micro pin grid array (MPGA). In addition, the pin contacts 44 can beused as the terminal contacts for the component 16, for surface mountingthe component 16, or for stacking the component 16 in stacked electronicassemblies. The component 16 also includes the outer polymer layer 54,and the back side polymer layer 48.

Referring to FIGS. 3A-3E, different embodiments of the component 16(FIG. 2I) are illustrated. In FIG. 3A, a component 16A includes athinned die 10A, conductive members 38A, and back side pin contacts 44Aformed using a circuit side process substantially as previouslydescribed. In addition, the component 16A includes an outer polymerlayer 54A but no circuit side contacts. In this embodiment the pincontacts 44A are the terminal contacts for the component 16A, and permitthe component 16A to be surface mounted to a mating electronic elementsuch as a module substrate, a package substrate, a socket or a circuitboard.

In FIG. 3B, a component 16B includes a thinned die 10B, conductivemembers 38B and pin contacts 44B formed using a circuit side processsubstantially as previously described. In addition, the component 16Bincludes front side redistribution contacts 52B which comprise metalballs, such as solder balls or bumps, embedded in an outer polymer layer54B. The contacts 52B can be formed by forming or bonding metal bumps orballs to bonding pads 42B substantially as previously described. Inaddition, the contacts 52B can be used as terminal contacts and to flipchip mount the component 16B to a mating electronic element such as amodule substrate, a package substrate or a circuit board. The contacts52B can also be used for testing applications or to selectively addressthe integrated circuits 24 (FIG. 2J).

In FIG. 3C, a component 16C includes a thinned die 10C, conductivemembers 38C and pin contacts 44C formed using a circuit side processsubstantially as previously described. In addition, the component 16Cincludes front side contacts 50C which comprise metal balls, such assolder balls or bumps, embedded in an outer passivation layer 54C. Thecontacts 50C can be used as terminal contacts, and to flip chip mountthe component 16C to a mating electronic element such as a modulesubstrate, a package substrate or a circuit board. The contacts 50C canalso be used for testing applications, or to selectively address theintegrated circuits 24 (FIG. 2J).

In FIG. 3D, a component 16D includes a thinned die 10D, conductivemembers 38D and front side contacts 50D, which comprise metal balls,such as solder balls or bumps, embedded in an outer passivation layer54D. In addition, the component 16D includes back side contacts 60D inthe form of metal bumps or balls formed on pads 64D in electricalcommunication with the conductive members 38D. In this embodiment thedie 10D can be thinned by grinding or CMP, but not etched to expose theconductive members 38D as previously described. In addition, the pads64D can be formed using a suitable process such as patterning of a metallayer, and the conductive members 38D formed, or bonded, to the pads 64Dusing a suitable bonding or deposition process.

In FIG. 3E, a component 16E includes a thinned die 10E and back sidecontact pins 38E in electrical communication with conductive members 38Esubstantially as previously described. The component 16E also includesfront side pin contacts 62E formed on the conductive members 38E. Thefront side pin contacts 62E can comprise pins or stud bumps bonded tothe conductive members 38E using a wire bonder, a stud bumper or othersuitable apparatus. The pin contacts 62E can be used as terminalcontacts, test contacts or in stacked assemblies.

Referring to FIGS. 4A-4F and 5A-5F, steps in a fabrication method for analternate embodiment female component 16F (FIG. 5F) are illustrated.Initially as shown in FIGS. 4A and 5A, the wafer 12 containing thesemiconductor dice 10 having the die contacts 18 is provided. Inaddition, openings 28 are formed through the die contacts 18, and partway through the substrate 14, substantially as previously described.

Next, as shown in FIGS. 4B and 5B, the electrically insulatingpassivation layer 30 is formed on the circuit side 20, and theelectrically insulating passivation layer 32 are formed on sidewalls ofthe openings 28, substantially as previously described.

Next, as shown in FIGS. 4C and 5C, the passivation layers 30, 32 arepatterned to expose the exposed portions 34 of the die contacts 18substantially as previously described.

Next, as shown in FIGS. 4D and 5D, female conductive members 38F areformed in the openings 28, and redistribution conductors 40F are formedon the circuit side 20 in electrical communication with the conductivemembers 38F. However, in this embodiment the conductive members 38F donot completely fill the openings 28. Rather, the openings 28 and theconductive members 38F form through openings sized to electricallyengage the pin contacts 44, 44B (FIG. 2I) on adjacent components 16, 16Bin a stacked assembly 68C (FIG. 6C). The conductive members 38F can beformed in electrical communication with the die contacts 18 bydepositing a conductive layer on only the sidewalls of the electricallyinsulated openings 28. The same conductive layer can also form theredistribution conductors 40F, and can be deposited using an electrolessprocess, an electrolytic process or a CVD process substantially aspreviously described. Alternately, the conductive members 38F and theconductors 40F can be formed using separate processes. As anotheralternative, a conductive layer can be deposited to completely fill theopenings 28, and then etched to re-open or partially fill the openings28 and form the conductors 40F.

Next, as shown in FIGS. 4E and 5E, the substrate 14 is thinned,substantially as previously, described to expose the openings 28 and theconductive members 38F. In addition, a back side polymer layer 48F canbe formed on the thinned backside 22 substantially as previouslydescribed for back side polymer layer 48.

As also shown in FIGS. 4E and 5E, redistribution contacts 52F are formedon, or in electrical communication with, the conductors 40F. In thisembodiment the redistribution contacts 52F comprise planar pads formedusing a subtractive process (etching through a mask) or an additiveprocess (deposition through a mask). Alternately the redistributioncontacts 52F can comprise planarized bumps or balls, as previouslydescribed for redistribution contacts 52 (FIG. 2I). As also shown inFIGS. 4E and 5E, an outer insulating layer 54F can be formed on theconductors 40F substantially as previously described for outerinsulating layer 54.

Next as shown in FIGS. 4F, a singulating step is performed to singulatethe components 16F from the wafer 12 and from one another. Thesingulating step can be performed by attaching the wafer 12 to a dicingtape 56 and sawing grooves 58 through the wafer 12 substantially asprevious described.

As shown in FIG. 5F, a singulated component 16F includes the thinned die10 having the die contacts 18 in electrical communication with theintegrated circuits 24 (FIG. 2J) thereon. The component 16F alsoincludes the redistribution contacts 52F on the circuit side 20 inelectrical communication with the die contacts 18. The contacts 52F canbe used to selectively access the integrated circuits 24 for testing orother functions. In addition, for some applications the contacts 52F canbe used as the terminal contacts for the component 16F.

The component 16F also includes the conductive members 38F whichcomprise the plated openings 28 in electrical communication with the diecontacts 18. The conductive members 38F are configured to electricalengage the pin contacts 44, 44B (FIG. 2I) on adjacent components 16, 16Bin a stacked assembly 68C (FIG. 6C). The component 16F also includes theouter polymer layer 54F, and the back side polymer layer 48F.

Referring to FIGS. 6A-6C, electronic assemblies fabricated using thecomponents 16A-16F are illustrated. In FIG. 6A, a pin mount electronicassembly 68A includes a support substrate 70A and one or more components16A surface mounted to the supporting substrate 70A. The supportingsubstrate 70A can comprise a module substrate, a package substrate or acircuit board. In addition, the pin contacts 44A on the component 16Aare soldered or otherwise connected to mating contacts (not shown) onthe supporting substrate 70A.

In FIG. 6B, a flip chip electronic assembly 68B includes a supportsubstrate 70B, and one or more components 16B flip chip mounted to thesubstrate 70B. The support substrate 70B includes electrodes 72B and thecontacts 52B on the component 16B are bonded to the electrodes 72B.

In FIG. 6C, a stacked electronic assembly 68C includes a supportsubstrate 70C having electrodes 72C. The component 16B forms the lowertier of the stacked electronic assembly 68C, and includes contacts 52Bbonded to the electrodes 72C on the support substrate 70C. The femalecomponent 16F forms the middle tier of the stacked electronic assembly68C. In addition, the female conductive members 38F on the femalecomponent 16F physically and electrically engage the pin contacts 44B onthe component 16B. If desired, the pin contacts 44B can be bonded to thefemale conductive members 38F by soldering or other bonding process(e.g., conductive polymer adhesives). In addition, spacers (not shown)can be used to space the female component 16F from the component 16B.The component 16 forms the upper tier of the stacked electronic assembly68C with the female conductive members 38F on the female component 16Fphysically and electrically engaging the pin contacts 44 on thecomponent 16.

As another alternative, the double pin component 16E of FIG. 3E can besubstituted for the component 16B to form the lower tier of the stackedelectronic assembly 68C. Alternately other arrangements of thecomponents 16A-16F can be employed to form other stacked assemblies.

Thus the invention provides an improved semiconductor component, amethod for fabricating the component, and systems incorporating thecomponent. While the invention has been described with reference tocertain preferred embodiments, as will be apparent to those skilled inthe art, certain changes and modifications can be made without departingfrom the scope of the invention as defined by the following claims.

1. A method for fabricating a semiconductor component on a substratehaving a first side, a second side, at least one integrated circuit andat least one contact on the first side in electrical communication withthe integrated circuit comprising: forming an opening in the contactextending at least part way into the substrate to a depth; forming aconductive member in the opening in electrical communication with thecontact; and removing portions of the substrate from the second sidesuch that the substrate has a thickness less than the depth and anexposed terminal portion of the conductive member comprises a pincontact.
 2. The method of claim 1 wherein the removing step comprisesplanarizing and etching the substrate.
 3. The method of claim 1 furthercomprising forming a non-oxidizing layer on a tip of the terminalportion.
 4. The method of claim 1 further comprising stacking a secondsubstrate on the substrate having a plated opening electrically engagingthe pin contact.
 5. The method of claim 1 further comprising forming aconductor on the first side of the substrate in electrical communicationwith the conductive member, and forming a second contact on the firstside of the substrate in electrical communication with the conductor. 6.A method for fabricating a semiconductor component on a semiconductorsubstrate having a first side, a second side and a contact on the firstside comprising: forming an opening in the contact extending at leastpart way into the substrate; forming a conductive member in the openingin electrical communication with the contact; thinning the substratefrom the second side to expose a portion of the conductive member; andremoving portions of the substrate from the second side to expose aterminal portion of the conductive member as a pin contact.
 7. Themethod of claim 6 wherein the thinning step comprises mechanicalplanarization or chemical mechanical planarization and the removing stepcomprises etching.
 8. The method of claim 6 further comprising forming anon-oxidizing layer on a tip of the terminal portion.
 9. A method forfabricating a semiconductor component on a semiconductor substratehaving a first side, a second side, and a contact on the first sidecomprising: forming an opening in the contact extending at least partway into the substrate to a depth; forming a conductive member in theopening in electrical communication with the contact; thinning thesubstrate from the second side to a thickness less than the depth toexpose a terminal portion of the conductive member as a pin contact; andforming a conductor on the first side in electrical communication withthe conductive member and a second contact on the first side inelectrical communication with the conductor.
 10. The method of claim 9further comprising forming a non-oxidizing layer on a tip of theterminal portion.
 11. The method of claim 9 further comprising stackinga second substrate on the substrate having a plated opening electricallyengaging the pin contact.
 12. The method of claim 9 further comprisingforming a non-oxidizing layer on the terminal portion.